Radar Payload

Doppler radar payloads

Overview

The Doppler radar enables speed and direction measurement to be collected and added to events.

Hardware

See Radar for more information on selecting a radar unit.

The OPS243-A radar from OmniPreSense:

OmniPreSense’s OPS243 is complete short-range radar (SRR) solution providing motion detection, speed, direction, and range reporting. All radar signal processing is done on board and a simple API reports the processed data.

Software

The OPS243 radar sensors include an easy-to-use API interface for returning a variety of radar readings and calculated values in JSON format. By default, we capture all of these values in separate tables:

• DetectedObjectVelocity (command ON).

  • radar_dov table

  • Sensor determines if an object is present by looking for 2 consecutive speed reports. If met, the max speed detected is reported. If a faster speed is detected, additional speeds are reported. This lowers the number of speed reports for a given detected object. Use On to turn the mode off.

• TimedSpeedCounts (command @O).

  • radar_timed_speed_counts table.

  • Sensor counts and reports the cumulative number of objects (defined by DetectedObjectVelocity) that have gone by in a given period. Default TM setting is reporting every 300-seconds.

• Raw Speed Magnitude (command OS).

  • radar_raw_speed_magnitude table and radar_raw_speed_magnitude_single table

  • Reports magnitude and associated speed of each reading. The magnitude is a measure of the size, distance, and reflectivity of the object detected. By default, TM captures the 3-burst speed/magnitude pairs and the single strongest magnitude and associated speed in separate tables for deep dive and easier analysis, respectively.

• Vehicle Length (command OC).

  • Note: Requires Firmware OPS9243.

  • radar_oc_payload table

  • From the docs: Provides several parameters which can help identify the vehicle type and/or lane in which the vehicle is located. This includes start/end time, frames, min/max MPH, magnitude, and length calculations.

Radar Database

The following attributes are captured, by default, into tmdb.events.sqlite:

radar_dov table

Attribute	Description	SQLite data type	Valid values
time	Unix timestamp directly from radar	REAL	Unix timestamp in Seconds
unit	Unit of measure for velocity/speed set on radar (configurable)	TEXT	"mph"
direction	Object moving direction relative to radar placement; i.e. "outbound" is moving away from radar.	TEXT	"outbound" or "inbound"
velocity	Maximum speed/velocity calculated for all measurements object was detected in the radar zone. `DetectedObjectVelocity` from API	REAL	Integer, Positive, Negative corresponding to inbound and outbound direction, respectively
radarName	Radar sensor that captured the data. This field is used to associate with cameras and other radars.	TEXT
deployment_id	Each ID represents a unique deployment configuration and/or location for the device. This acts a foreign key link to the `deployment` table, `id` column.	TEXT, FOREIGN KEY	`deployment`.`id` foreign key, may be null

radar_timed_speed_counts table

Attribute	Description	SQLite data type	Valid values
time	Unix timestamp directly from radar	REAL	Unix timestamp in Seconds
direction	Object moving direction relative to radar placement; i.e. "outbound" is moving away from radar.	TEXT	"outbound" or "inbound"
units	Unit of measure for velocity/speed set on radar (configurable)	TEXT	"mph"
count	Number of object detection (DOV) measurements; should correspond to number of objects/vehicles that passed through radar zone	INTEGER	Integer, positive
average	Average speed/velocity across all object detections (count) during measurement interval; defined by `units` attribute	REAL	Integer, Positive, Negative corresponding to inbound and outbound direction, respectively
radarName	Radar sensor that captured the data. This field is used to associate with cameras and other radars.	TEXT
deployment_id	Each ID represents a unique deployment configuration and/or location for the device. This acts a foreign key link to the `deployment` table, `id` column.	TEXT, FOREIGN KEY	`deployment`.`id` foreign key, may be null

radar_raw_speed_magnitude table

Attribute	Description	SQLite data type	Valid values
time	Unix timestamp directly from radar	REAL	Unix timestamp in Seconds
unit	Unit of measure for velocity/speed set on radar (configurable)	TEXT	"mph"
magnitude	Array of individual magnitude measurements for the sampling time depending on K+ setting; e.g. one speed represents ~50-ms at 20k samples. Corresponds to speed's array location in descending order of speed (configurable).	TEXT	Positive
speed	Array of individual Speed/velocity for the sampling time depending on K+ setting; e.g. one speed represents ~50-ms at 20k samples. Corresponds to magnitude's array location in descending order of speed (configurable).	REAL	Positive, Negative corresponding to inbound and outbound direction, respectively
radarName	Radar sensor that captured the data. This field is used to associate with cameras and other radars.	TEXT
deployment_id	Each ID represents a unique deployment configuration and/or location for the device. This acts a foreign key link to the `deployment` table, `id` column.	TEXT, FOREIGN KEY	`deployment`.`id` foreign key, may be null

radar_raw_speed_magnitude_single table

Attribute	Description	SQLite data type	Valid values
time	Unix timestamp directly from radar	REAL	Unix timestamp in Seconds
unit	Unit of measure for velocity/speed set on radar (configurable)	TEXT	"mph"
magnitude	Array of individual magnitude measurements for the sampling time depending on K+ setting; e.g. one speed represents ~50-ms at 20k samples. Corresponds to speed's array index==0 in descending order of speed (configurable).	REAL	Positive
speed	Array of individual Speed/velocity for the sampling time depending on K+ setting; e.g. one speed represents ~50-ms at 20k samples. Corresponds to magnitude's array index==0 in descending order of speed (configurable).	REAL	Positive, Negative corresponding to inbound and outbound direction, respectively
radarName	Radar sensor that captured the data. This field is used to associate with cameras and other radars.	TEXT
deployment_id	Each ID represents a unique deployment configuration and/or location for the device. This acts a foreign key link to the `deployment` table, `id` column.	TEXT, FOREIGN KEY	`deployment`.`id` foreign key, may be null

radar_oc_payload table

Attribute	Description	SQLite data type	Valid values
start_time	Unix timestamp directly from radar	REAL	Unix timestamp in Seconds
end_time	Unix timestamp directly from radar	REAL	Unix timestamp in Seconds
delta_time_msec	Different in end and start times in milliseconds, representing the amount of time the object was in the radar zone: i.e. `end_time` minus `start_time` * 1000	REAL
direction	Object moving direction relative to radar placement; i.e. "outbound" is moving away from radar.	TEXT	inbound, outbound
frames_count	Number of frames, defined by doppler pings (equivalent to OS) for an object through the field of view (FOV)	INTEGER
velocity_max	Maximum velocity/speed of object through field of view (FOV)	REAL
velocity_min	Minimum velocity/speed of object through field of view (FOV)	REAL
magnitude_max	Maximium magnitude of doppler radar response of object through field of view (FOV)	REAL
magnitude_mean	Average / mean magnitude of doppler radar response of object through field of view (FOV)	REAL
velocity_change	Delta max_speed – min_speed. This can help with indication of the lane a vehicle is in. A vehicle farther to the edge of the FoV will have a higher cosine error change and therefore delta speed. This should be normalized to speed so offline we’ve used (max_speed – min_speed)/max_speed. A lower number tends to show a vehicle in the farther lane over.	REAL
frames_per_velocity	Number of frames captured per unit of velocity. This acts as the inverse to speed in order to calculate length of object. Calculated as `frames_count / velocity_max`	REAL
object_length	Estimted length of object, calculated by taking speed and time through field of view.	REAL
units	Velocity unit of measurement. Will also match length units, relatively.	TEXT	mph, mps - for Miles Per Hour (imperial) and Meters Per Second (metric), respectively
object_label	RESERVE FOR FUTURE USE. Radar-based classification for the type of object that moved through the field of view. This is estimated from common roadway-based objects. Payload is a JSON object containing key:value of the top -calculated labels and respective likelihood score.	TEXT, JSON	JSON object with key:value pairs; e.g. {"car": 0.86, "bike": 0.25, "person": 0.10}
radarName	Radar sensor that captured the data. This field is used to associate with cameras and other radars.	TEXT
deployment_id	Each ID represents a unique deployment configuration and/or location for the device. This acts a foreign key link to the `deployment` table, `id` column.	TEXT, FOREIGN KEY	`deployment`.`id` foreign key, may be null